6 files changed, 29 insertions, 1 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index dd00fd556a60..67473849f20e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -164,6 +164,10 @@ and is between 256 and 4096 characters. It is defined in the file
         acpi_skip_timer_override [HW,ACPI]
                         Recognize and ignore IRQ0/pin2 Interrupt Override.
                         For broken nForce2 BIOS resulting in XT-PIC timer.
+        acpi_use_timer_override [HW,ACPI}
+                        Use timer override. For some broken Nvidia NF5 boards
+                        that require a timer override, but don't have
+                        HPET
 
         acpi_dbg_layer= [HW,ACPI]
                         Format: <int>
diff --git a/arch/i386/kernel/acpi/boot.c b/arch/i386/kernel/acpi/boot.c
index 22e4c466e5a3..d12fb97a5337 100644
--- a/arch/i386/kernel/acpi/boot.c
+++ b/arch/i386/kernel/acpi/boot.c
@@ -82,6 +82,7 @@ EXPORT_SYMBOL(acpi_strict);
 acpi_interrupt_flags acpi_sci_flags __initdata;
 int acpi_sci_override_gsi __initdata;
 int acpi_skip_timer_override __initdata;
+int acpi_use_timer_override __initdata;
 
 #ifdef CONFIG_X86_LOCAL_APIC
 static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE;
@@ -1300,6 +1301,13 @@ static int __init parse_acpi_skip_timer_override(char *arg)
         return 0;
 }
 early_param("acpi_skip_timer_override", parse_acpi_skip_timer_override);
+
+static int __init parse_acpi_use_timer_override(char *arg)
+{
+        acpi_use_timer_override = 1;
+        return 0;
+}
+early_param("acpi_use_timer_override", parse_acpi_use_timer_override);
 #endif /* CONFIG_X86_IO_APIC */
 
 static int __init setup_acpi_sci(char *s)
diff --git a/arch/i386/kernel/acpi/earlyquirk.c b/arch/i386/kernel/acpi/earlyquirk.c
index fe799b11ac0a..c9841692bb7c 100644
--- a/arch/i386/kernel/acpi/earlyquirk.c
+++ b/arch/i386/kernel/acpi/earlyquirk.c
@@ -27,11 +27,17 @@ static int __init check_bridge(int vendor, int device)
 #ifdef CONFIG_ACPI
         /* According to Nvidia all timer overrides are bogus unless HPET
            is enabled. */
-        if (vendor == PCI_VENDOR_ID_NVIDIA) {
+        if (!acpi_use_timer_override && vendor == PCI_VENDOR_ID_NVIDIA) {
                 nvidia_hpet_detected = 0;
                 acpi_table_parse(ACPI_HPET, nvidia_hpet_check);
                 if (nvidia_hpet_detected == 0) {
                         acpi_skip_timer_override = 1;
+                          printk(KERN_INFO "Nvidia board "
+                       "detected. Ignoring ACPI "
+                       "timer override.\n");
+                printk(KERN_INFO "If you got timer trouble "
+                                 "try acpi_use_timer_override\n");
+
                 }
         }
 #endif
diff --git a/arch/x86_64/kernel/early-quirks.c b/arch/x86_64/kernel/early-quirks.c
index 2b1245d86258..68273bff58cc 100644
--- a/arch/x86_64/kernel/early-quirks.c
+++ b/arch/x86_64/kernel/early-quirks.c
@@ -45,7 +45,13 @@ static void nvidia_bugs(void)
         /*
          * All timer overrides on Nvidia are
          * wrong unless HPET is enabled.
+         * Unfortunately that's not true on many Asus boards.
+         * We don't know yet how to detect this automatically, but
+         * at least allow a command line override.
          */
+        if (acpi_use_timer_override)
+                return;
+
         nvidia_hpet_detected = 0;
         acpi_table_parse(ACPI_HPET, nvidia_hpet_check);
         if (nvidia_hpet_detected == 0) {
@@ -53,6 +59,8 @@ static void nvidia_bugs(void)
                 printk(KERN_INFO "Nvidia board "
                        "detected. Ignoring ACPI "
                        "timer override.\n");
+                printk(KERN_INFO "If you got timer trouble "
+                        "try acpi_use_timer_override\n");
         }
 #endif
         /* RED-PEN skip them on mptables too? */
diff --git a/include/asm-i386/acpi.h b/include/asm-i386/acpi.h
index 6016632d032f..c80b3a94511a 100644
--- a/include/asm-i386/acpi.h
+++ b/include/asm-i386/acpi.h
@@ -132,6 +132,7 @@ extern int acpi_gsi_to_irq(u32 gsi, unsigned int *irq);
 
 #ifdef CONFIG_X86_IO_APIC
 extern int acpi_skip_timer_override;
+extern int acpi_use_timer_override;
 #endif
 
 static inline void acpi_noirq_set(void) { acpi_noirq = 1; }
diff --git a/include/asm-x86_64/acpi.h b/include/asm-x86_64/acpi.h
index ed59aa4c6ff9..9d1916e59c04 100644
--- a/include/asm-x86_64/acpi.h
+++ b/include/asm-x86_64/acpi.h
@@ -163,6 +163,7 @@ extern u8 x86_acpiid_to_apicid[];
 #define ARCH_HAS_POWER_INIT 1
 
 extern int acpi_skip_timer_override;
+extern int acpi_use_timer_override;
 
 #endif /*__KERNEL__*/